Şen, Y.Ekmekçi, İsmail2019-08-212019-08-212016https://hdl.handle.net/11467/2900In this study, horizontal global solar radiation estimation models and estimated values are reviewed and compared with measured national database for Istanbul. The mathematical models used are based on the sunshine duration data as common in the world. For comparisons, the most common statistical methods (MBE, MPE and RMSE) are also used. We came up with the result that solar radiation and sunshine duration measurements in Turkey are very unreliable and inaccurate.eninfo:eu-repo/semantics/openAccessConference Object